Nano and micro scale particles carrying therapeutic agents and delivered into or within close proximity of the tumor in vivo can play a significant role in increasing the effectiveness of the treatment while decreasing severity of side effects. Such techniques would be highly relevant, particularly, for organs that are difficult to access because of a variety of biological barriers, including those developed by tumors. For example, nanoparticles are capable of crossing the blood-brain barrier due to their small size and thus are an excellent candidate for non-invasive treatment of brain tumors.
The possible clinical use of magnetically guided medicine-carriers for drug delivery to tumors and elsewhere within the body has been studied for decades, but has not become very useful. In fact, the leading company in this field, FeRx Corporation, collapsed in 2005, due to their failed clinical trials on liver cancers, which demonstrated how incompetent current magnetic targeting is, for internal organs.
Conventional magnetic targeting employs magnetic-attraction. It uses DMC (dipolar medicine carriers). Such DMC always align their magnetic polarities to the magnetic field, and are always pulled toward an external magnet regardless of the polarity of the external magnetic field applied. When you pulling such DMC to a target, those DMC in the front move faster because they are closer to the pulling source and those lag behind move slower, and those further behind may get lost, due to the magnetic strength decreases exponentially with distance. The more you pull these DMC, the more they spread over. Tumors close to the skin or a joint might be OK because the skin or joint can stop the spread-over, but deep tumors like those in the brain and liver are not.
There is no way to focus such DMC to a tumor with magnetic-attraction, you have to inject in large quantities; causing the price unaffordable. The second is that the DMC attract each other and may aggregate into a blot, hence blocking the blood flowing in the vessel and causing similarities to strokes and heart attacks. The third is that the DMC are hardly movable, not maneuverable, and cannot be recovered; most of these DMC are left behind permanently in the human body after the treatment, hence causing Ferro liver failure over times, and limiting them for terminally ill patients only. The DMC can only be concentrated below the skin and near a joint, and it has been previously shown that magnetic direction of chemotherapy coated ferrofluid is effective in surface tumors, but it does not work for deep tissue tumors, such as of a depth of 30 cm or greater.
In one word, the conventional drug carriers along with the magnetic-attraction can only do 2-dimensional-magnetic-targeting. 3D-magnetic-targeting is urgently needed but scientists consider it as temping and impossible.
Although artificial unipolar magnets have been invented, such as Herb's toy bail (U.S. Pat. No. 4,874,346) which is built by many magnetic bars that point with their one same poles to the core and the other to the surface, making the whole surface unipolar, we have not found anyone prepared any unipolar particles that are in the micro or nano scale.
We propose PMC (Pushable Medicine Carriers), such as the UMC can be pushed around with magnetic repulsion. As shown in FIG. 4, a hulk magnet, ‘5’, repels a UMC, ‘1’ with its like pole, N pole.
Because the PMC can be pushed around with magnetic-repulsion, they can be used for 3D-tumor-targeting (3-dimensional magnetic targeting or 3D-magnetic-targeting). When you push in-vivo PMC to a tumor with an external magnet, those lag behind move faster because they are closer to the external magnet, and those move in the front move slower, causing the PMC concentrated. You can thus concentrate the PMC as a locus or swamp, push and relocate the locus to different target-tumors, and shape the locus to tumors, for 3D-Tumor-Targeting as shown in FIG. 2, even focus the locus into micro-scale tumors for microsurgeries.
Such 3D-tumor-targeting is very useful: (1) It enables MRI to identify micro-scale tumors and quantities their masses, The PMC can serve as contrast agents for MRI to detect micro-scale tumors so to be able to non-invasively detect tumors at an early stage for maximum therapeutic benefit. For breast cancer, for instance, the goal of molecular imaging is to be able to accurately diagnose when the tumor mass has approximately 100-1000 cells, as opposed to the current techniques like mammography, which require more than a million cells for accurate clinical diagnosis. (2) it enables noninvasive microsurgeries because PMC can be focused to tiny areas with magnetic repulsion. This is the only way to go for noninvasive microsurgeries. And most importantly, (3) it opens the door for therapies to cure cancers, such as for IR-thermal-ablation to destroy tumors (FIG. 5), even micro-scale tumors, and for hyperthermia-treatment to clear up cancer-cells in specific regions. Infrared radiation, ‘7’ in FIG. 5, at 800-1020 nm, will penetrate tissues and heat only the PMC, ‘1’, which, in turn, will heat the cancerous area, ‘6’. At around 45° C., cancer cells will be killed and normal cells will survive, which is called Hyperthermia treatment. At around 55° C., a tumor will be totally destroyed, which is called thermal ablation. Destroying tumors, including micro-scale ones, one after another can completely clear up the cancer from a patient. The patient will be cured.
UMC (Unipolar Medicine Carriers) will not cause similarities of heart-attacks and strokes; their concentrations are easily maneuverable: you can have a higher concentration in one tumor by pushing them closer together and a lower concentration in another tumor by allowing them to spread over; UMC spread evenly in a tumor; and UMC can be retrieved after a treatment, all because UMC repel each other and do not aggregate.
The invention is good for all kinds of cancers and illnesses, such as prostate cancer, enlarged prostate, brain tumor, liver cancer, lung cancer, etc, you name it.